recently replaced roof. original cedar shakes, then layer of heavy, green shingles, then two layers of black asphalt.... does anyone know how old the heavy, thick, green shingles would be? Black base, material impregnated into that, about 1/8" thick.

annsdanen,....

The fasteners on the cedar should be square cut nails from the early 1900s or before,....that to me, would put the heavy green shingles in the early 30s` 40s`.

The heavy matting is an all organic shingle that does not contain fiberglass or membrains. It is multiple layers of asphault soaked papers fused together, then the colored sunblocking grainuals are pressure rolled onto the hot matt. Useually, three tab (slots) or jets(no slots).

That`s why they are thick, and might have roof nails with really big nailheads.